> What do you mean by that? I looked at the glibc resolver,> it might be that if getaddrinfo() does not get proper> ai_family arguments of AF_INET, it will accept AAAA records.> So, the application which thinks is using IPv4 DNS resolving> will eventually connect using IPv6?

The original reason for using getaddrinfo was to make applications
IPv6-aware. In order to push at least some traffic over IPv6,
getaddrinfo implementations typically prefer IPv6 over IPv4. However,
this comes into play only if the name has got an AAAA in the first
place, which is still rare (except perhaps for DNS and mail servers).